Validation of oscillometric blood pressure measurement using a Datex S/5 Compact multiparameter monitor in anaesthetized adult dogs.

OBJECTIVE: To compare noninvasive (NIBP) with invasive blood pressure (IBP) measurements from a Datex S/5 Compact monitor in anaesthetized adult dogs, and to evaluate it according to the American College of Veterinary Internal Medicine (ACVIM) and the Association for the Advancement of Medical Instrumentation (AAMI) criteria. STUDY DESIGN: Prospective clinical study. ANIMALS: A group of 34 client-owned adult dogs. METHODS: Dogs were anaesthetized for different surgical procedures using different anaesthetic protocols. IBP was measured using a catheter placed in a dorsal pedal artery. A blood pressure cuff was placed over the contralateral dorsal pedal artery for NIBP measurement. Data were recorded using the Datex iCollect program, and paired readings were matched every 3 minutes for 60 minutes. Bland-Altman and error grid analyses were used to estimate the agreement between IBP and NIBP measurements, and its clinical significance, respectively. Data were reported as mean bias [lower, upper limits of agreement (LoA)]. RESULTS: The Datex S/5 monitor conformed to most ACVIM criteria. The correlation coefficient was less than 0.9 for systolic, diastolic, and mean arterial pressures (MAP). The best agreement between the noninvasive and invasive methods was observed for MAP, with LoA (-17 to 13 mmHg) and higher percentage of NIBP readings within 5 (55.6%), 10 (81.7%) and 20 (98.6%) mmHg of the IBP values. The Datex S/5 NIBP technology did not meet the AAMI validation criteria and less than 95% of the paired measurements were found within the green zone of the error grid analysis. CONCLUSIONS AND CLINICAL RELEVANCE: The Datex S/5 monitor conformed to most ACVIM criteria but not with the more rigorous AAMI standards. Despite good agreement between IBP and NIBP for MAP measurements, care must be taken when using this device to guide therapeutic interventions of blood pressure in anaesthetized healthy adult dogs.

Disposable Airway Pressure Manometers for Endotracheal Tube Cuff Inflation.

This study aimed to assess the performance, accuracy, precision and repeatability of two single-use airway pressure manometers as a cost-effective alternative for inflation of endotracheal tubes with high-volume, low-pressure cuffs. The manometers were tested in a bench top model against a U-tube manometer. Eighteen units of each device were tested. Three consecutive measurements were performed at pressures of 20, 25 and 30 cmH2O each. The mean ± SD of the recorded pressures and maximum deviation from the target pressures were calculated for each device and each target pressure. For device A, the mean ± SD pressures were 19.6 ± 0.7, 23.6 ± 0.8 and 28.3 ± 0.8 cmH2O; for device B, the mean ± SD pressures were 19.3 ± 0.6, 24.3 ± 0.9 and 29.2 ± 0.67 cmH2O for target pressures of 20, 25 and 30 cmH2O, respectively. The bias for device A was -0.4, -1.4, and -1.7 cmH2O and for device B, -0.7, -0.7, and -0.8 cmH2O for target pressures of 20, 25, and 30 cmH2O, respectively. Both devices showed results comparable to those reported for commercial cuff manometers. They represent inexpensive tools that provide clinically sufficient accuracy, precision and repeatability for ETT cuff inflation between pressures of 20 and 30 cmH2O.

Comparison of the effects of propofol and alfaxalone on the electrocardiogram of dogs, with particular reference to QT interval.

Cardiac electrical activity is often altered by administration of anesthetic drugs. While the effects of propofol in this regard have previously been described in dogs, to date, there are no reports of the effect of alfaxalone. This study investigated the impact of both propofol and alfaxalone on the ECG of 60 dogs, after premedication with acepromazine and methadone. Heart rate increased significantly in both groups. The PR and QRS intervals were significantly increased following propofol while with alfaxalone the QRS duration was significantly increased and ST segment depression was observed. The QT and JT interval were significantly shorter following induction with alfaxalone, but, when corrected (c) for heart rate, QTc and JTc in both groups were significantly greater following induction. When comparing the magnitude of change between groups, the change in RR interval was greater in the alfaxalone group. The change in both QT and JT intervals were significantly greater following alfaxalone, but when QTc and JTc intervals were compared, there were no significant differences between the two drugs. The similarly increased QTc produced by both drugs may suggest comparable proarrhythmic effects.

Renin-angiotensin system inhibitors reduce the progression of mesangioproliferative glomerulonephritis: 10 year follow-up.

BACKGROUND: Proteinuria is a common presentation of mesangioproliferative glomerulonephritis (MsPGN). No studies are available on the long-term effect of treatment by renin-angiotensin system (RAS) inhibitors on renal outcome in MsPGN patients. This study prospectively evaluates the effects of RAS inhibitors on renal outcome in patients with low risk MsPGN followed up for 10 years using historical patients with similar features at the time of presentation as untreated controls. ENDPOINTS: decrease of basal proteinuria>20% and loss>20% of basal glomerular filtrate rate (GFR) at the end of first year of observation. The patients were re-evaluated bimonthly during the first year and every 6 months thereafter. RESULTS: Twenty-five patients fulfilled the selection criteria. After one year follow-up 19 patients reached the endpoint of proteinuria and no patient reached the endpoint of GFR. No significant change in blood pressure levels (BP) and GFR was registered, by contrast daily proteinuria decreased significantly (p<0.001), falling by 29% at sixth month and 47% at the end of the follow-up. The historical control group consisted of 15 untreated patients seen between 1987 and 1992. The two-way analysis of variance for repeated measures showed greater values of GFR (p<0.001) and lower levels of daily proteinuria (p<0.001) in treated patients as compared to untreated controls. CONCLUSIONS: This 10-year follow-up study indicates that the early treatment with RAS inhibitors at low doses favourably influences the long-term renal outcome in proteinuric patients with MsPGN. Limitations were the small sample size and lack of randomization.